复合内嵌筋材加固混凝土梁破坏模式分析

The Failure Modes of Reinforced Concrete Beams Strengthened with Multiple Near-surface Mounted Bars

对螺旋肋钢筋施加预应力,将其与碳纤维筋组合后,以不同的方式嵌入到混凝土梁受拉区混凝土保护层中,对混凝土梁进行加固,能显著提高混凝土梁的承载能力。在对承载能力试验结果做简单阐述的前提下,针对加固梁中多材料、多界面存在的客观现实,全面系统地分析了加固梁可能存在的破坏模式,且与试验梁的破坏模式进行对比,对不同加固方式加固的试验梁的破坏模式及破坏机理进行了分析。分析表明,多界面的存在严重影响了加固梁的承载力;不同的破坏界面,应对加固材料断面总内力采取不同的取值,在试验中应特别注意破坏界面的判别,否则计算结果会产生很大误差。

The bearing capacity of reinforced concrete（RC） beams strengthened with near-surface mounted carbon fiber reinforced plastic（CFRP） and pre-stressed helical rib bar can be increased significantly in comparison with the un-reinforced beams.Firstly,this paper simply presents the bearing capacity results of seven reinforced concrete beams strengthened with near-surface mounted CFRP and pre-stressed helical rib bar,and then,the failure modes of strengthened beams including multiple materials and interfaces are analyzed systematically.Compared with the possible failure modes,the failure modes and the failure mechanism of the strengthened beams are analyzed.The analyzing results indicate that the bearing capacity of strengthened beams are seriously influenced by the interfaces,different failure modes correspond with the section total force of the strengthening material,and the judgment of failure interface should be careful,otherwise,the error of calculating results would be very great.